Die-punch.



Patented nec. 25, |900.

a. c. Amswumu.

DIE PUNCH.

(Application Bled Dec. 18, 1899.1

(No Modem wi lm @on eo maren.

UNITED STATES PATENT OFFICE.

GEORGE c. AiNswoRrI-I, or RooKLiNE, MASSACHUSETTS.

DIE-PUNCH.

SPECIFICATION-forming part of Letters Patent N. 664,523, dai-,ed December 25, 1900;

Application filed December 18, 1399. bel'al N. 740,794.` (No model.)

To @ZZ whom it may con/cern.'

Be it known that I, GEORGE C. AINswoRTH, a ycitizen of `the United States, residing at Brookline, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Die-Punches; and I do hereby declare the following t0 be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Myinvention relates to hand-punches, and more particularly to that class of punches used by dentists in preparing the sheet-rubber dams used in certain dental operations and commonly known as rubber-dam punches. Itis with a view of improving upon the rubber-dam punches now in use that I have evolved the present invention, which I will .now describe in detail, referring by letter to the drawings accompanying and forming a part of this specification and in which I have illustrated my invention, pointing out in the claims at the end of this description the novel features which are of my invention.

While I have shown my invention as applied to a rubber-dam punch and in the detailed description hereinafter shall describe a Apunch of this type, I do not wish to be understood as limiting my invention to this particular type of punch, for it will be obvious that my invention is applicable to punches designed for other purposes with equally satisfactory results.

In the drawings, in which like characters refer to corresponding parts in the several views, Figure 1 is a side view of a punch embodying myimprovements, said punch being shown in open position. Fig 2 is a side View, partly in section, of the punch closed, the male die member or plunger of the upper jaw engaging one of the said die-openings in the female die member, die-block, or disk carried by the lower jaw, a piece of sheet-rubber bsing shown in position between the jaws. Fig. 3 is a plan view of the punch with the upper jaw broken away to show the relation of the die-block and its centering and locking spring. Fig. 4 is a detail sectional view, on an enlarged scale, of the jaws and the dies thereon. Fig. 5 is a detail view in plan, on an enlarged scale, of the die-block and its centering and locking spring, the spring being showdin full lines in its normal position and in dotted lines' in the position it occupies when the punch is closed.

The punch shown in the drawings consists of two members ct a', pivoted together at b in the ordinary manner, said members ad hav#r ing grips or handles of the ordinary or any preferred construction and having a male die member or plunger and a female die member or die-block at their respective forward ends. The forward ends orjaws c c of the said punch members ot a are long, slender, and iiexible, the object of this being twofold. First, the lengthened forward ends c c' of the said punch members a d' admit of a perforation being made in the sheet of rubber or material to be punched or perforated at a distance somewhat removed from the edge of the material, as is sometimes necessary or de* sirable, without bunching or crowdingthe material between the jaws of the punch and perhaps interfering with the ready operation of the same, (see Fig. 2,) and, second, the exible ends when the plunger and die-block carried thereby are forc'ed together' will be iiexed or sprung, (see dotted lines in Fig. 2,) so as to allow the point of the rigid plunger to seat itself accurately in the die-opening e in the die-block e and make a clean cut or perforation through the material, as clearly shown in Fig. 4. jaws c c' flexible the accurate seating or engagement of the die members is quickly and easily effected and that without exerting a great amount of pressure on the punch, this being due to the fact that both of the jaws c c flexing slightly will cause the point of the male die member d to ride into and seat itself accurately and in complete cutting contact with a die-hole in the die-block e' with much greater ease than where the exure or bend-` ing is in one jaw only and without subjecting the male plunger to undue strain, as is the case where the male die member or plunger is sprung or flexed to bring it to proper position. The said plunger or male member d ofthe cutting-die is of ordinary construction, with the exception that its point d is round or convex instead of cone-shaped, as usual, the rounded end d' of the plunger d seating itself more accurately and with less liability I find that by making both of the IOO to mar or injure the die-holes in the die-block than a cone-shaped plunger, it being obvious that since the plunger does not descend in a straight or right line, but moves in the arc of a circle, the center of which is the pivot of the two members a a' of the punch, the various sized die-holes in the die block, with which the plunger coacts, must be formed in said die-block at different distances from its center to insure the perfect registry or centering of the point of the plunger with each of them, and such perfect registry and complete contact of the plunger-point with the entire cutting edge of a die-hole are essential to insure a clean cut or perforation. When a cone-shaped plunger is used, it is a matter of some difficulty to accurately position the several die-holes of different diameters so as that the sharp cone-point Will enter a die-hole accurately exactly in the center and in complete contact with the edge of the.diehole and not mar or injure the cutting edge. By making the plunger d with a rounded or conveX point d, however, the several die-holes in the die-block may be made at substantially the same distance from the center, for said rounded end d'will contact with the entire edge of a die-hole even though the dieholefbe not accurately centered beneath the line of movement of said plunger d, and that without any danger o f injuring the die-block or straining and breaking the plunger.

The die-block or female member e of the cutting-die is in a general way similar to those now in use, preferably being pivoted at e2 to the lower jaw c of the punch so as that it may be rotated to bring any one of the several dieholes e into position beneath the plunger d,

the said lower jaw having the usual opening or clearer e3 in its end beneath the die-holes. l In order that the punch may not be closed except when some one of the several dieholes e is in position to be entered by the plunger d and to insure the proper centering of a die-hole beneath the plunger, I provide an automatic centering and locking device which consists in the present instance of a bow-springf, secured at one end to the'upper jaw c by a screw or rivet, said springf curving back intothe bite of the jaws a ct and having a free end f', which bears against and slides freely upon the inner face of the lower jaw c' of the punch. Said spring tends to hold the jaw members c c separated, and the said free end f of the spring is provided with a slot f2, through which passes a headed screw or pin f3, said pin forming a sliding connection between the spring and jaw which not only serves to keep the spring f in position between the jaws, but prevents said jaws c c4- from being swung wide open, it being apparent that the cutting devices used need be separated but slightly for most classes of work, andwhere the members of the punch are maintained in a substantially closed position, as by the spring f, the handles of the punch are always in such close relation to each other as to be readily grasped and m anip; ulated. The free end f' of said spring f is pointed or V-shaped, as shown, so as that said free end f as it slides forward when the punch is closed will enter and engage one of a series of notches or indentations e4, formed in the periphery of the die-block or disk c', and allow the punch to be closed and the plunger d to seat itself in one of the die-holes e, said notches e4 having outwardly-flaring Sides. These notches or indentations e4 are preferably diametrically opposite the several die-holes e, and it is obvious that unless the die-block e be in such position that the descending plunger d registers with some one of the die-holes e the free end f' of the springf will strike against the periphery of the dieblock and prevent closing of the punch, thereby guarding against injury to the male or female members of the die on account of inaccurate registry of the parts. If, however, some one of the said die-holes eis in position beneath the plunger d, the end f of said springf will enter the corresponding notch in the periphery of said disk e, center said disk, lock it elfectually against movement in either direction, and allow the die members to engage and perforate the material. It will be seen, Fig. 5, vthat the V-shaped point of the free end f of said spring f projects far enough into the notches e4 of the die-block to prevent the spinning or easy turning of the said block, so as that when a particular hole in the die-block has been brought beneath the plunger it will remain in such position until it is desirable to utilize one lof the other die-holes, when the die-block e' may be turned, so as to cause the free end of the springf to ride over the intervening projections between the notches e4 and allow it to engage another notch. The flaring or rounded sides of the said notches e4 admit of the ready turning of the die-block e and at the same time will cause lthe accurate positioning of said dieblock when the jaws are closed a-nd the V- shapedpoint ofthe end f of said spring fenters and centers itself in one of the notches e4, for if the die-block e be slightly out of positionthe point of the spring striking the flaring side of the notch will throw the dieblock to a position of accurate adjustment with a die-hole inpperfect registry with the plunger.

It will be seen that the springfis of sufficient width to till and cover the rear end or joint of the jaw-opening, being curved back so as to form a guard and prevent any possibility of the material being punched getting caught in lthe joint of the jaws and cut or mutilated, an occurrence which would be especially objectionable where a rubber sheet for dental use was being punched.

It is believed that the operation of the punch will be apparent from the foregoing description of its construction, and it is therefore deemed unnecessary to give a detailed rehearsal of its action.

IIO

I do not wish to be understood as limitingmyself to the exact construction and arrangement Vof parts shown and described, since the construction may be varied to a considerable extent within the province of mechanical skill without departing from the spirit of my invention.

Having described my invention, I claim and desire to secure by Letters Patentl. A diepunch comprising two pivoted members, having comparatively longjaw portions, a female die carried by one of said jaws, and a male die member or plunger carried by the other jaw, both of said jaws being flexible to allow said male die member or plunger to seat itself accurately and incomplete cutting contact.

2. A die punch comprising two pivoted members having comparatively longjaw portions, a rotatable female die-block having a plurality of die-holes therein carried by one jaw, and a rigid male die member or plunger carried by the other jaw, said jaws being exible to allow said male die member to seat itself accurately and in complete cutting contact with a die-hole in said female die-block.

3. In adie-punch, the combination with two pivoted members having jaw portions, of a movable female die-block having a plurality of die-holes carried by one of said jaws; a male member or plunger carried by the other jaw, and means actuated by the closing of the jaws and coperating with said female die-block to prevent complete closing of said jaws and contact of said die members until the movable die-block is in position to receive the male member in one of its die-holes.

4. In adie-punch, the combination with two pivoted members having jaw portions, of a .rotatable female die-block having a plurality of die-holes carried by one of said jaws; a

male member or plunger carried by the other jaw, and means actuated by the closing of the jaws and coperating with said female die-block to prevent complete closing of said jaws and contact of said die members until the said rotatable die-block is in position to receive the male memberin one of its die-holes.

5. In a die-punch, the combination with two pivoted members having jaw portions, of a rotatable female die-block having a plurality of die-holes carried by one of said jaws; a rigid male member carried by the other jaw, said jaws being flexible to allow accurate seating and complete cutting contact of said die members, and means actuated by the closing of the jaws and coperating with said female die-block to prevent complete closing of the jaws and contact of said die members until the said rotatable die-block is in position to receive the male member in one of its dieholes.

6. [n adie-punch, the combination with two pivoted members having jaw portions, of a movable female die-block carried by one of said jaws, a male member or plunger carried by the other jaw, and means independent of said male member and actuated by the closing of the jaws to automatically center said movable die-block in accurate positionbeneath said male member,said centeringmeans serving also to lock said movable die-block against movement in either direction.

7. In a diepunch, the combination with two pivoted members having jaw portions, of a movable female die-block carried by one of said jaws; a rigid male member or plunger carried by the other jaw, said jaws being flexible to allow accurate seating and complete cutting contact of said die members, and means independent of said male die member to automatically center and lock said movable die-block in accurate position beneath said male member by the closing of the jaws.

8. In adie-punch, the combination with two pivoted members having jaw portions, of a movable female die-block carried by one of said jaws and provided with a plurality of die-holes, a male die member or plunger carried by the other jaw, and a spring actuated by the closing of the jaws to engage said movable die-block and automatically center it beneath said male member or plunger, said spring serving also to lock said movable dieblock against movement in either direction.

9. In a die-punch, the combination with two pivoted members having jaw portions, of a movable female die-block carried by one of said jaws and provided with a plurality of die-holes, a male die member or plunger carried by the other jaw, Vand means independent of said male die member and actuated 'by the closing of the jaws to automatically engage and center said movable die-block in accurate position beneath the male die member, said means serving also to both lock said movable die-block against movement in either direction and to prevent complete closing of the jaws and contact of said die members when the die members are out of register with each other.

lO. In a die-punch, the combination with4 two pivoted members having jaw portions, of a movable female die-block carried by one of said jaws and provided witha plurality of die-holes, a male die member or plunger carriedby the other jaw, and a spring between said jaws and actuated by the closing of the jaws to automatically engage and center said movable die-block in accurate position beneath the male die member or plunger, said spring serving also to both lock said movable die-block against movement in either direction and to prevent complete closing of the jaws and contact of the die member when said die members are out of register with each other.

1l. In a die-punch, the combination with two pivoted members having jaw portions, of a rotatable female die member pivoted to one of said jaws and provided with a plurality of die-holes, a rigid male member carried by the other jaw, 'a spring lying between said jaws and secured at one end to the male-die-supporting jaw, its other end sliding freely `on the other jaw and engaging one of a series of notches or indentations in the periphery of said die-block on closing the punch, to lock said die-block in accurate position beneath said male member.

12. In a die-punch, the combination with two pivoted members having jaw portions, of a rotatable female die-block pivoted on one of said jaws and provided with a plurality of die-holes, a rigid male member carried by the other jaw, a spring lying between said jaws and secured at one end to the male-.die-supporting jaw, its other end sliding freely .on the other jaw and engaging one of a series .of flaring notches or indentations in the periphery of said die-'block on closing the punch, to automatically center and lock said die block in accurate position beneath said male' member.

13. In a die-punch, the combination with two pivoted members having jaw portions, of a rotatable female die-block carried by one of said jaws, a male die member or plunger carried by the other jaw, a spring lying between said jaws and secured at one end to the maledie-supporting jaw, and means for securing said spring to the other jaw so that it may 4have a limited movement thereon, said spring alix my signature 35 

